It appears the Michigan football team is going with a youth movement on defense.

Coach Brady Hoke announced Friday night in a video released by the school that true freshman Desmond Morgan has supplanted Brandin Hawthorne as the starting weak-side linebacker for the No. 17 Wolverines (6-1, 2-1), who face Purdue (4-3, 2-1) at noon Saturday on ESPN2.

Freshmen Brennen Beyer (strong-side linebacker), Frank Clark (defensive end) and Blake Countess (cornerback) already were mentioned this week by Hoke as guys who could play a more pronounced role after Michigan sat idle last week. Hoke added Morgan and freshman cornerback Raymon Taylor to that list Friday.

That's five freshmen, then, who used the off week to state their cases for larger roles — and they all play defense.

Morgan is one of the biggest surprises of the bunch, as he officially replaces Hawthorne as the starter at weak-side linebacker. Hawthorne had started the past five games.

He played well early, but his performance tapered in recent weeks.

Morgan, a 6-foot-1, 220-pound freshman from Holland, Mich., replaced Hawthorne for much of the Wolverines' last game against Michigan State and made four tackles. He's appeared in six games overall.

"We think Desmond has a great future here, and he’s doing a lot of good things," Hoke said in the video. "We’re excited about that."

Countess' growing role, on the other hand, is more expected.

The standout freshman from Baltimore has played exceptionally since making his defensive debut against Eastern Michigan. In the next game against San Diego State, he recorded a team-high seven tackles.

Countess has 24 on the season, which is sixth most on the team despite receiving limited snaps early in the season. He has played more in recent weeks, though, including all but the first few snaps against Michigan State.

"All I know is that when he’s gone in there, he’s played without a conscience," defensive coordinator Greg Mattison said recently, "and I think when you’re a corner you have to play that way.

"I think he has that ‘it’ factor (where he thinks), ‘OK, I’m going to go out there and I’m going to do what you tell me to do, and if it doesn’t go right, then I’m going to come back the next play.’"

Countess' time has come at the expense of senior cornerback Troy Woolfolk, who remains the starter despite his diminishing role. That trend could persist, as Hoke said Countess will "play an awful lot" against Purdue.

He also said another freshman corner, Taylor, could enter the equation as well.

When asked if there was anyone else whose role could grow this week, Hoke said: "We’ll see what Ray Taylor does."

So far, the 5-foot-10, 169-pound freshman from Highland Park, Mich., has played mostly in nickel packages and on special teams. He has appeared in five games.

Meantime, Clark seems to be challenging Craig Roh and Jibreel Black for time at rush end, and Beyer is battling another freshman, Jake Ryan, at strong-side linebacker.

"When they first got here for fall camp, they were two guys we thought, for true freshmen, had some really raw athleticism and potential," senior defensive lineman Ryan Van Bergen said earlier this week.

Van Bergen said Clark and Beyer entered fall camp ahead of schedule, especially when it came to the intellect it takes to play in Mattison's 4-3 defense. That helped expedite their progress.

"Both of them were well-coached in high school, to the point where they were able to pick up the scheme," Van Bergen said. "Schematically, they were able to figure out things relatively quickly, as fast as you can expect a freshman to pick it up.

"I think you’ll see more and more contribution out of them."

Van Bergen said Clark is one of the fastest players on the defense.

Kyle Meinke covers Michigan football for AnnArbor.com. He can be reached at 734-623-2588, by email at kylemeinke@annarbor.com and followed on Twitter @kmeinke.